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<div class="title">opennurbs_qsort_template.h</div>  </div>
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<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno">    1</span>&#160;<span class="comment">// NOTE: 14 April 2011 Dale Lear:</span></div>
<div class="line"><a name="l00002"></a><span class="lineno">    2</span>&#160;<span class="comment">//    Replace this code with Mikko&#39;s &quot;quacksort&quot;, once &quot;quacksort&quot; is fully debugged</span></div>
<div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160;<span class="comment">//    This code is based ont the VC 2010 crt qsort.c file and must not be released</span></div>
<div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160;<span class="comment">//    with public opennurbs.</span></div>
<div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160; </div>
<div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="preprocessor">#if !defined(ON_COMPILING_OPENNURBS_QSORT_FUNCTIONS)</span></div>
<div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;<span class="comment">/*</span></div>
<div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;<span class="comment">See opennurbs_sort.cpp for examples of using openurbs_qsort_template.c</span></div>
<div class="line"><a name="l00009"></a><span class="lineno">    9</span>&#160;<span class="comment">to define type specific quick sort functions.</span></div>
<div class="line"><a name="l00010"></a><span class="lineno">   10</span>&#160;<span class="comment">*/</span></div>
<div class="line"><a name="l00011"></a><span class="lineno">   11</span>&#160;<span class="preprocessor">#error Do not compile openurbs_qsort_template.c directly.</span></div>
<div class="line"><a name="l00012"></a><span class="lineno">   12</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00013"></a><span class="lineno">   13</span>&#160; </div>
<div class="line"><a name="l00014"></a><span class="lineno">   14</span>&#160;<span class="preprocessor">#define ON_QSORT_CUTOFF 8            </span><span class="comment">/* testing shows that this is good value */</span><span class="preprocessor"></span></div>
<div class="line"><a name="l00015"></a><span class="lineno">   15</span>&#160; </div>
<div class="line"><a name="l00016"></a><span class="lineno">   16</span>&#160;<span class="comment">/* Note: the theoretical number of stack entries required is</span></div>
<div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;<span class="comment">   no more than 1 + log2(num).  But we switch to insertion</span></div>
<div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;<span class="comment">   sort for CUTOFF elements or less, so we really only need</span></div>
<div class="line"><a name="l00019"></a><span class="lineno">   19</span>&#160;<span class="comment">   1 + log2(num) - log2(CUTOFF) stack entries.  For a CUTOFF</span></div>
<div class="line"><a name="l00020"></a><span class="lineno">   20</span>&#160;<span class="comment">   of 8, that means we need no more than 30 stack entries for</span></div>
<div class="line"><a name="l00021"></a><span class="lineno">   21</span>&#160;<span class="comment">   32 bit platforms, and 62 for 64-bit platforms. */</span></div>
<div class="line"><a name="l00022"></a><span class="lineno">   22</span>&#160;<span class="preprocessor">#define ON_QSORT_STKSIZ (8*sizeof(void*) - 2)</span></div>
<div class="line"><a name="l00023"></a><span class="lineno">   23</span>&#160; </div>
<div class="line"><a name="l00024"></a><span class="lineno">   24</span>&#160; </div>
<div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;<span class="comment">// ON_SORT_TEMPLATE_TYPE -&gt; double, int, ....</span></div>
<div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;<span class="preprocessor">#if !defined(ON_SORT_TEMPLATE_TYPE)</span></div>
<div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;<span class="preprocessor">#error Define ON_SORT_TEMPLATE_TYPE macro before including opennurbs_qsort_template.c</span></div>
<div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160; </div>
<div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;<span class="preprocessor">#if !defined(ON_QSORT_FNAME)</span></div>
<div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;<span class="preprocessor">#error Define ON_QSORT_FNAME macro before including opennurbs_qsort_template.c</span></div>
<div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160; </div>
<div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;<span class="preprocessor">#if defined(ON_SORT_TEMPLATE_COMPARE)</span></div>
<div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;<span class="comment">// use a compare function like strcmp for char* strings</span></div>
<div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;<span class="preprocessor">#define ON_QSORT_GT(A,B) ON_SORT_TEMPLATE_COMPARE(A,B) &gt; 0</span></div>
<div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;<span class="preprocessor">#define ON_QSORT_LE(A,B) ON_SORT_TEMPLATE_COMPARE(A,B) &lt;= 0</span></div>
<div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;<span class="preprocessor">#define ON_QSORT_EQ(A,B) ON_SORT_TEMPLATE_COMPARE(A,B) == 0</span></div>
<div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;<span class="preprocessor">#else</span></div>
<div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;<span class="comment">// use type compares</span></div>
<div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;<span class="preprocessor">#define ON_QSORT_GT(A,B) *A &gt; *B</span></div>
<div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;<span class="preprocessor">#define ON_QSORT_LE(A,B) *A &lt;= *B</span></div>
<div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;<span class="preprocessor">#define ON_QSORT_EQ(A,B) *A == *B</span></div>
<div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160; </div>
<div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;<span class="preprocessor">#if defined(ON_SORT_TEMPLATE_USE_MEMCPY)</span></div>
<div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;<span class="preprocessor">#define ON_QSORT_SWAP(A,B) memcpy(&amp;tmp,A,sizeof(tmp));memcpy(A,B,sizeof(tmp));memcpy(B,&amp;tmp,sizeof(tmp))</span></div>
<div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;<span class="preprocessor">#else</span></div>
<div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;<span class="preprocessor">#define ON_QSORT_SWAP(A,B) tmp = *A; *A = *B; *B = tmp</span></div>
<div class="line"><a name="l00050"></a><span class="lineno">   50</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160; </div>
<div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;<span class="keyword">static</span> <span class="keywordtype">void</span> ON_shortsort(ON_SORT_TEMPLATE_TYPE *, ON_SORT_TEMPLATE_TYPE *);</div>
<div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;<span class="keyword">static</span> <span class="keywordtype">void</span> ON_shortsort(ON_SORT_TEMPLATE_TYPE *lo, ON_SORT_TEMPLATE_TYPE *hi)</div>
<div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;{</div>
<div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;  ON_SORT_TEMPLATE_TYPE *p;</div>
<div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;  ON_SORT_TEMPLATE_TYPE *max;</div>
<div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;  ON_SORT_TEMPLATE_TYPE tmp;</div>
<div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160; </div>
<div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;  <span class="comment">/* Note: in assertions below, i and j are alway inside original bound of</span></div>
<div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;<span class="comment">      array to sort. */</span></div>
<div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160; </div>
<div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;  <span class="keywordflow">while</span> (hi &gt; lo)</div>
<div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;  {</div>
<div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;    <span class="comment">/* A[i] &lt;= A[j] for i &lt;= j, j &gt; hi */</span></div>
<div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;    max = lo;</div>
<div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;    <span class="keywordflow">for</span> (p = lo+1; p &lt;= hi; p++)</div>
<div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;    {</div>
<div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;      <span class="comment">/* A[i] &lt;= A[max] for lo &lt;= i &lt; p */</span></div>
<div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;      <span class="keywordflow">if</span> ( ON_QSORT_GT(p,max) )</div>
<div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;      {</div>
<div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160;          max = p;</div>
<div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;      }</div>
<div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;      <span class="comment">/* A[i] &lt;= A[max] for lo &lt;= i &lt;= p */</span></div>
<div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160;    }</div>
<div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160; </div>
<div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;    <span class="comment">/* A[i] &lt;= A[max] for lo &lt;= i &lt;= hi */</span></div>
<div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160; </div>
<div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;    ON_QSORT_SWAP(max,hi);</div>
<div class="line"><a name="l00079"></a><span class="lineno">   79</span>&#160; </div>
<div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;    <span class="comment">/* A[i] &lt;= A[hi] for i &lt;= hi, so A[i] &lt;= A[j] for i &lt;= j, j &gt;= hi */</span></div>
<div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160; </div>
<div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;    hi--;</div>
<div class="line"><a name="l00083"></a><span class="lineno">   83</span>&#160; </div>
<div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;    <span class="comment">/* A[i] &lt;= A[j] for i &lt;= j, j &gt; hi, loop top condition established */</span></div>
<div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;  }</div>
<div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;  <span class="comment">/* A[i] &lt;= A[j] for i &lt;= j, j &gt; lo, which implies A[i] &lt;= A[j] for i &lt; j,</span></div>
<div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;<span class="comment">      so array is sorted */</span></div>
<div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;}</div>
<div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160; </div>
<div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;<span class="comment">/* this parameter defines the cutoff between using quick sort and</span></div>
<div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;<span class="comment">   insertion sort for arrays; arrays with lengths shorter or equal to the</span></div>
<div class="line"><a name="l00092"></a><span class="lineno">   92</span>&#160;<span class="comment">   below value use insertion sort */</span></div>
<div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160; </div>
<div class="line"><a name="l00094"></a><span class="lineno">   94</span>&#160;<span class="preprocessor">#if defined(ON_SORT_TEMPLATE_STATIC_FUNCTION)</span></div>
<div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;<span class="keyword">static</span></div>
<div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160;<span class="keywordtype">void</span> </div>
<div class="line"><a name="l00098"></a><span class="lineno">   98</span>&#160;ON_QSORT_FNAME (</div>
<div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;    ON_SORT_TEMPLATE_TYPE *base,</div>
<div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160;    <span class="keywordtype">size_t</span> num</div>
<div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160;    )</div>
<div class="line"><a name="l00102"></a><span class="lineno">  102</span>&#160;{</div>
<div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;  ON_SORT_TEMPLATE_TYPE *lo;                   <span class="comment">/* start of sub-array currently sorting */</span></div>
<div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;  ON_SORT_TEMPLATE_TYPE *hi;                   <span class="comment">/* end of sub-array currently sorting */</span></div>
<div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;  ON_SORT_TEMPLATE_TYPE *mid;                  <span class="comment">/* points to middle of subarray */</span></div>
<div class="line"><a name="l00106"></a><span class="lineno">  106</span>&#160;  ON_SORT_TEMPLATE_TYPE *loguy;                <span class="comment">/* traveling pointers for partition step */</span></div>
<div class="line"><a name="l00107"></a><span class="lineno">  107</span>&#160;  ON_SORT_TEMPLATE_TYPE *higuy;                <span class="comment">/* traveling pointers for partition step */</span></div>
<div class="line"><a name="l00108"></a><span class="lineno">  108</span>&#160;  ON_SORT_TEMPLATE_TYPE *lostk[ON_QSORT_STKSIZ];</div>
<div class="line"><a name="l00109"></a><span class="lineno">  109</span>&#160;  ON_SORT_TEMPLATE_TYPE *histk[ON_QSORT_STKSIZ];</div>
<div class="line"><a name="l00110"></a><span class="lineno">  110</span>&#160;  <span class="keywordtype">size_t</span> size;                <span class="comment">/* size of the sub-array */</span></div>
<div class="line"><a name="l00111"></a><span class="lineno">  111</span>&#160;  <span class="keywordtype">int</span> stkptr;                 <span class="comment">/* stack for saving sub-array to be processed */</span></div>
<div class="line"><a name="l00112"></a><span class="lineno">  112</span>&#160;  ON_SORT_TEMPLATE_TYPE tmp;</div>
<div class="line"><a name="l00113"></a><span class="lineno">  113</span>&#160; </div>
<div class="line"><a name="l00114"></a><span class="lineno">  114</span>&#160;  <span class="keywordflow">if</span> ( 0 == base || num &lt; 2 )</div>
<div class="line"><a name="l00115"></a><span class="lineno">  115</span>&#160;    <span class="keywordflow">return</span>;</div>
<div class="line"><a name="l00116"></a><span class="lineno">  116</span>&#160; </div>
<div class="line"><a name="l00117"></a><span class="lineno">  117</span>&#160;  stkptr = 0;                 <span class="comment">/* initialize stack */</span></div>
<div class="line"><a name="l00118"></a><span class="lineno">  118</span>&#160; </div>
<div class="line"><a name="l00119"></a><span class="lineno">  119</span>&#160;  lo = base;</div>
<div class="line"><a name="l00120"></a><span class="lineno">  120</span>&#160;  hi = base + (num-1);        <span class="comment">/* initialize limits */</span></div>
<div class="line"><a name="l00121"></a><span class="lineno">  121</span>&#160; </div>
<div class="line"><a name="l00122"></a><span class="lineno">  122</span>&#160;  <span class="comment">/* this entry point is for pseudo-recursion calling: setting</span></div>
<div class="line"><a name="l00123"></a><span class="lineno">  123</span>&#160;<span class="comment">      lo and hi and jumping to here is like recursion, but stkptr is</span></div>
<div class="line"><a name="l00124"></a><span class="lineno">  124</span>&#160;<span class="comment">      preserved, locals aren&#39;t, so we preserve stuff on the stack */</span></div>
<div class="line"><a name="l00125"></a><span class="lineno">  125</span>&#160;recurse:</div>
<div class="line"><a name="l00126"></a><span class="lineno">  126</span>&#160; </div>
<div class="line"><a name="l00127"></a><span class="lineno">  127</span>&#160;  size = (hi - lo) + 1;        <span class="comment">/* number of el&#39;s to sort */</span></div>
<div class="line"><a name="l00128"></a><span class="lineno">  128</span>&#160; </div>
<div class="line"><a name="l00129"></a><span class="lineno">  129</span>&#160;  <span class="comment">/* below a certain size, it is faster to use a O(n^2) sorting method */</span></div>
<div class="line"><a name="l00130"></a><span class="lineno">  130</span>&#160;  <span class="keywordflow">if</span> (size &lt;= ON_QSORT_CUTOFF) </div>
<div class="line"><a name="l00131"></a><span class="lineno">  131</span>&#160;  {</div>
<div class="line"><a name="l00132"></a><span class="lineno">  132</span>&#160;      ON_shortsort(lo, hi);</div>
<div class="line"><a name="l00133"></a><span class="lineno">  133</span>&#160;  }</div>
<div class="line"><a name="l00134"></a><span class="lineno">  134</span>&#160;  <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00135"></a><span class="lineno">  135</span>&#160;    <span class="comment">/* First we pick a partitioning element.  The efficiency of the</span></div>
<div class="line"><a name="l00136"></a><span class="lineno">  136</span>&#160;<span class="comment">        algorithm demands that we find one that is approximately the median</span></div>
<div class="line"><a name="l00137"></a><span class="lineno">  137</span>&#160;<span class="comment">        of the values, but also that we select one fast.  We choose the</span></div>
<div class="line"><a name="l00138"></a><span class="lineno">  138</span>&#160;<span class="comment">        median of the first, middle, and last elements, to avoid bad</span></div>
<div class="line"><a name="l00139"></a><span class="lineno">  139</span>&#160;<span class="comment">        performance in the face of already sorted data, or data that is made</span></div>
<div class="line"><a name="l00140"></a><span class="lineno">  140</span>&#160;<span class="comment">        up of multiple sorted runs appended together.  Testing shows that a</span></div>
<div class="line"><a name="l00141"></a><span class="lineno">  141</span>&#160;<span class="comment">        median-of-three algorithm provides better performance than simply</span></div>
<div class="line"><a name="l00142"></a><span class="lineno">  142</span>&#160;<span class="comment">        picking the middle element for the latter case. */</span></div>
<div class="line"><a name="l00143"></a><span class="lineno">  143</span>&#160; </div>
<div class="line"><a name="l00144"></a><span class="lineno">  144</span>&#160;    mid = lo + (size / 2);      <span class="comment">/* find middle element */</span></div>
<div class="line"><a name="l00145"></a><span class="lineno">  145</span>&#160; </div>
<div class="line"><a name="l00146"></a><span class="lineno">  146</span>&#160;    <span class="comment">/* Sort the first, middle, last elements into order */</span></div>
<div class="line"><a name="l00147"></a><span class="lineno">  147</span>&#160;    <span class="keywordflow">if</span> ( ON_QSORT_GT(lo,mid) ) {ON_QSORT_SWAP(lo,mid);}</div>
<div class="line"><a name="l00148"></a><span class="lineno">  148</span>&#160;    <span class="keywordflow">if</span> ( ON_QSORT_GT(lo,hi)  ) {ON_QSORT_SWAP(lo,hi);}</div>
<div class="line"><a name="l00149"></a><span class="lineno">  149</span>&#160;    <span class="keywordflow">if</span> ( ON_QSORT_GT(mid,hi) ) {ON_QSORT_SWAP(mid,hi);}</div>
<div class="line"><a name="l00150"></a><span class="lineno">  150</span>&#160; </div>
<div class="line"><a name="l00151"></a><span class="lineno">  151</span>&#160;    <span class="comment">/* We now wish to partition the array into three pieces, one consisting</span></div>
<div class="line"><a name="l00152"></a><span class="lineno">  152</span>&#160;<span class="comment">        of elements &lt;= partition element, one of elements equal to the</span></div>
<div class="line"><a name="l00153"></a><span class="lineno">  153</span>&#160;<span class="comment">        partition element, and one of elements &gt; than it.  This is done</span></div>
<div class="line"><a name="l00154"></a><span class="lineno">  154</span>&#160;<span class="comment">        below; comments indicate conditions established at every step. */</span></div>
<div class="line"><a name="l00155"></a><span class="lineno">  155</span>&#160; </div>
<div class="line"><a name="l00156"></a><span class="lineno">  156</span>&#160;    loguy = lo;</div>
<div class="line"><a name="l00157"></a><span class="lineno">  157</span>&#160;    higuy = hi;</div>
<div class="line"><a name="l00158"></a><span class="lineno">  158</span>&#160; </div>
<div class="line"><a name="l00159"></a><span class="lineno">  159</span>&#160;    <span class="comment">/* Note that higuy decreases and loguy increases on every iteration,</span></div>
<div class="line"><a name="l00160"></a><span class="lineno">  160</span>&#160;<span class="comment">        so loop must terminate. */</span></div>
<div class="line"><a name="l00161"></a><span class="lineno">  161</span>&#160;    <span class="keywordflow">for</span> (;;)</div>
<div class="line"><a name="l00162"></a><span class="lineno">  162</span>&#160;    {</div>
<div class="line"><a name="l00163"></a><span class="lineno">  163</span>&#160;      <span class="comment">/* lo &lt;= loguy &lt; hi, lo &lt; higuy &lt;= hi,</span></div>
<div class="line"><a name="l00164"></a><span class="lineno">  164</span>&#160;<span class="comment">          A[i] &lt;= A[mid] for lo &lt;= i &lt;= loguy,</span></div>
<div class="line"><a name="l00165"></a><span class="lineno">  165</span>&#160;<span class="comment">          A[i] &gt; A[mid] for higuy &lt;= i &lt; hi,</span></div>
<div class="line"><a name="l00166"></a><span class="lineno">  166</span>&#160;<span class="comment">          A[hi] &gt;= A[mid] */</span></div>
<div class="line"><a name="l00167"></a><span class="lineno">  167</span>&#160; </div>
<div class="line"><a name="l00168"></a><span class="lineno">  168</span>&#160;      <span class="comment">/* The doubled loop is to avoid calling comp(mid,mid), since some</span></div>
<div class="line"><a name="l00169"></a><span class="lineno">  169</span>&#160;<span class="comment">          existing comparison funcs don&#39;t work when passed the same</span></div>
<div class="line"><a name="l00170"></a><span class="lineno">  170</span>&#160;<span class="comment">          value for both pointers. */</span></div>
<div class="line"><a name="l00171"></a><span class="lineno">  171</span>&#160; </div>
<div class="line"><a name="l00172"></a><span class="lineno">  172</span>&#160;      <span class="keywordflow">if</span> (mid &gt; loguy) </div>
<div class="line"><a name="l00173"></a><span class="lineno">  173</span>&#160;      {</div>
<div class="line"><a name="l00174"></a><span class="lineno">  174</span>&#160;          <span class="keywordflow">do</span>  {</div>
<div class="line"><a name="l00175"></a><span class="lineno">  175</span>&#160;              loguy++;</div>
<div class="line"><a name="l00176"></a><span class="lineno">  176</span>&#160;          } <span class="keywordflow">while</span> (loguy &lt; mid &amp;&amp; ON_QSORT_LE(loguy,mid));</div>
<div class="line"><a name="l00177"></a><span class="lineno">  177</span>&#160;      }</div>
<div class="line"><a name="l00178"></a><span class="lineno">  178</span>&#160;      <span class="keywordflow">if</span> (mid &lt;= loguy) </div>
<div class="line"><a name="l00179"></a><span class="lineno">  179</span>&#160;      {</div>
<div class="line"><a name="l00180"></a><span class="lineno">  180</span>&#160;          <span class="keywordflow">do</span>  {</div>
<div class="line"><a name="l00181"></a><span class="lineno">  181</span>&#160;              loguy++;</div>
<div class="line"><a name="l00182"></a><span class="lineno">  182</span>&#160;          } <span class="keywordflow">while</span> (loguy &lt;= hi &amp;&amp; ON_QSORT_LE(loguy,mid));</div>
<div class="line"><a name="l00183"></a><span class="lineno">  183</span>&#160;      }</div>
<div class="line"><a name="l00184"></a><span class="lineno">  184</span>&#160; </div>
<div class="line"><a name="l00185"></a><span class="lineno">  185</span>&#160;      <span class="comment">/* lo &lt; loguy &lt;= hi+1, A[i] &lt;= A[mid] for lo &lt;= i &lt; loguy,</span></div>
<div class="line"><a name="l00186"></a><span class="lineno">  186</span>&#160;<span class="comment">          either loguy &gt; hi or A[loguy] &gt; A[mid] */</span></div>
<div class="line"><a name="l00187"></a><span class="lineno">  187</span>&#160; </div>
<div class="line"><a name="l00188"></a><span class="lineno">  188</span>&#160;      <span class="keywordflow">do</span>  {</div>
<div class="line"><a name="l00189"></a><span class="lineno">  189</span>&#160;          higuy--;</div>
<div class="line"><a name="l00190"></a><span class="lineno">  190</span>&#160;      } <span class="keywordflow">while</span> (higuy &gt; mid &amp;&amp; ON_QSORT_GT(higuy,mid));</div>
<div class="line"><a name="l00191"></a><span class="lineno">  191</span>&#160; </div>
<div class="line"><a name="l00192"></a><span class="lineno">  192</span>&#160;      <span class="comment">/* lo &lt;= higuy &lt; hi, A[i] &gt; A[mid] for higuy &lt; i &lt; hi,</span></div>
<div class="line"><a name="l00193"></a><span class="lineno">  193</span>&#160;<span class="comment">          either higuy == lo or A[higuy] &lt;= A[mid] */</span></div>
<div class="line"><a name="l00194"></a><span class="lineno">  194</span>&#160; </div>
<div class="line"><a name="l00195"></a><span class="lineno">  195</span>&#160;      <span class="keywordflow">if</span> (higuy &lt; loguy)</div>
<div class="line"><a name="l00196"></a><span class="lineno">  196</span>&#160;          <span class="keywordflow">break</span>;</div>
<div class="line"><a name="l00197"></a><span class="lineno">  197</span>&#160; </div>
<div class="line"><a name="l00198"></a><span class="lineno">  198</span>&#160;      <span class="comment">/* if loguy &gt; hi or higuy == lo, then we would have exited, so</span></div>
<div class="line"><a name="l00199"></a><span class="lineno">  199</span>&#160;<span class="comment">          A[loguy] &gt; A[mid], A[higuy] &lt;= A[mid],</span></div>
<div class="line"><a name="l00200"></a><span class="lineno">  200</span>&#160;<span class="comment">          loguy &lt;= hi, higuy &gt; lo */</span></div>
<div class="line"><a name="l00201"></a><span class="lineno">  201</span>&#160; </div>
<div class="line"><a name="l00202"></a><span class="lineno">  202</span>&#160;      ON_QSORT_SWAP(loguy,higuy);</div>
<div class="line"><a name="l00203"></a><span class="lineno">  203</span>&#160; </div>
<div class="line"><a name="l00204"></a><span class="lineno">  204</span>&#160;      <span class="comment">/* If the partition element was moved, follow it.  Only need</span></div>
<div class="line"><a name="l00205"></a><span class="lineno">  205</span>&#160;<span class="comment">          to check for mid == higuy, since before the swap,</span></div>
<div class="line"><a name="l00206"></a><span class="lineno">  206</span>&#160;<span class="comment">          A[loguy] &gt; A[mid] implies loguy != mid. */</span></div>
<div class="line"><a name="l00207"></a><span class="lineno">  207</span>&#160; </div>
<div class="line"><a name="l00208"></a><span class="lineno">  208</span>&#160;      <span class="keywordflow">if</span> (mid == higuy)</div>
<div class="line"><a name="l00209"></a><span class="lineno">  209</span>&#160;          mid = loguy;</div>
<div class="line"><a name="l00210"></a><span class="lineno">  210</span>&#160; </div>
<div class="line"><a name="l00211"></a><span class="lineno">  211</span>&#160;      <span class="comment">/* A[loguy] &lt;= A[mid], A[higuy] &gt; A[mid]; so condition at top</span></div>
<div class="line"><a name="l00212"></a><span class="lineno">  212</span>&#160;<span class="comment">          of loop is re-established */</span></div>
<div class="line"><a name="l00213"></a><span class="lineno">  213</span>&#160;    }</div>
<div class="line"><a name="l00214"></a><span class="lineno">  214</span>&#160; </div>
<div class="line"><a name="l00215"></a><span class="lineno">  215</span>&#160;    <span class="comment">/*     A[i] &lt;= A[mid] for lo &lt;= i &lt; loguy,</span></div>
<div class="line"><a name="l00216"></a><span class="lineno">  216</span>&#160;<span class="comment">            A[i] &gt; A[mid] for higuy &lt; i &lt; hi,</span></div>
<div class="line"><a name="l00217"></a><span class="lineno">  217</span>&#160;<span class="comment">            A[hi] &gt;= A[mid]</span></div>
<div class="line"><a name="l00218"></a><span class="lineno">  218</span>&#160;<span class="comment">            higuy &lt; loguy</span></div>
<div class="line"><a name="l00219"></a><span class="lineno">  219</span>&#160;<span class="comment">        implying:</span></div>
<div class="line"><a name="l00220"></a><span class="lineno">  220</span>&#160;<span class="comment">            higuy == loguy-1</span></div>
<div class="line"><a name="l00221"></a><span class="lineno">  221</span>&#160;<span class="comment">            or higuy == hi - 1, loguy == hi + 1, A[hi] == A[mid] */</span></div>
<div class="line"><a name="l00222"></a><span class="lineno">  222</span>&#160; </div>
<div class="line"><a name="l00223"></a><span class="lineno">  223</span>&#160;    <span class="comment">/* Find adjacent elements equal to the partition element.  The</span></div>
<div class="line"><a name="l00224"></a><span class="lineno">  224</span>&#160;<span class="comment">        doubled loop is to avoid calling comp(mid,mid), since some</span></div>
<div class="line"><a name="l00225"></a><span class="lineno">  225</span>&#160;<span class="comment">        existing comparison funcs don&#39;t work when passed the same value</span></div>
<div class="line"><a name="l00226"></a><span class="lineno">  226</span>&#160;<span class="comment">        for both pointers. */</span></div>
<div class="line"><a name="l00227"></a><span class="lineno">  227</span>&#160; </div>
<div class="line"><a name="l00228"></a><span class="lineno">  228</span>&#160;    higuy++;</div>
<div class="line"><a name="l00229"></a><span class="lineno">  229</span>&#160;    <span class="keywordflow">if</span> (mid &lt; higuy) {</div>
<div class="line"><a name="l00230"></a><span class="lineno">  230</span>&#160;        <span class="keywordflow">do</span>  {</div>
<div class="line"><a name="l00231"></a><span class="lineno">  231</span>&#160;            higuy--;</div>
<div class="line"><a name="l00232"></a><span class="lineno">  232</span>&#160;        } <span class="keywordflow">while</span> (higuy &gt; mid &amp;&amp; ON_QSORT_EQ(higuy,mid));</div>
<div class="line"><a name="l00233"></a><span class="lineno">  233</span>&#160;    }</div>
<div class="line"><a name="l00234"></a><span class="lineno">  234</span>&#160;    <span class="keywordflow">if</span> (mid &gt;= higuy) {</div>
<div class="line"><a name="l00235"></a><span class="lineno">  235</span>&#160;        <span class="keywordflow">do</span>  {</div>
<div class="line"><a name="l00236"></a><span class="lineno">  236</span>&#160;            higuy--;</div>
<div class="line"><a name="l00237"></a><span class="lineno">  237</span>&#160;        } <span class="keywordflow">while</span> (higuy &gt; lo &amp;&amp; ON_QSORT_EQ(higuy,mid));</div>
<div class="line"><a name="l00238"></a><span class="lineno">  238</span>&#160;    }</div>
<div class="line"><a name="l00239"></a><span class="lineno">  239</span>&#160; </div>
<div class="line"><a name="l00240"></a><span class="lineno">  240</span>&#160;    <span class="comment">/* OK, now we have the following:</span></div>
<div class="line"><a name="l00241"></a><span class="lineno">  241</span>&#160;<span class="comment">          higuy &lt; loguy</span></div>
<div class="line"><a name="l00242"></a><span class="lineno">  242</span>&#160;<span class="comment">          lo &lt;= higuy &lt;= hi</span></div>
<div class="line"><a name="l00243"></a><span class="lineno">  243</span>&#160;<span class="comment">          A[i]  &lt;= A[mid] for lo &lt;= i &lt;= higuy</span></div>
<div class="line"><a name="l00244"></a><span class="lineno">  244</span>&#160;<span class="comment">          A[i]  == A[mid] for higuy &lt; i &lt; loguy</span></div>
<div class="line"><a name="l00245"></a><span class="lineno">  245</span>&#160;<span class="comment">          A[i]  &gt;  A[mid] for loguy &lt;= i &lt; hi</span></div>
<div class="line"><a name="l00246"></a><span class="lineno">  246</span>&#160;<span class="comment">          A[hi] &gt;= A[mid] */</span></div>
<div class="line"><a name="l00247"></a><span class="lineno">  247</span>&#160; </div>
<div class="line"><a name="l00248"></a><span class="lineno">  248</span>&#160;    <span class="comment">/* We&#39;ve finished the partition, now we want to sort the subarrays</span></div>
<div class="line"><a name="l00249"></a><span class="lineno">  249</span>&#160;<span class="comment">        [lo, higuy] and [loguy, hi].</span></div>
<div class="line"><a name="l00250"></a><span class="lineno">  250</span>&#160;<span class="comment">        We do the smaller one first to minimize stack usage.</span></div>
<div class="line"><a name="l00251"></a><span class="lineno">  251</span>&#160;<span class="comment">        We only sort arrays of length 2 or more.*/</span></div>
<div class="line"><a name="l00252"></a><span class="lineno">  252</span>&#160; </div>
<div class="line"><a name="l00253"></a><span class="lineno">  253</span>&#160;    <span class="keywordflow">if</span> ( higuy - lo &gt;= hi - loguy ) {</div>
<div class="line"><a name="l00254"></a><span class="lineno">  254</span>&#160;        <span class="keywordflow">if</span> (lo &lt; higuy) {</div>
<div class="line"><a name="l00255"></a><span class="lineno">  255</span>&#160;            lostk[stkptr] = lo;</div>
<div class="line"><a name="l00256"></a><span class="lineno">  256</span>&#160;            histk[stkptr] = higuy;</div>
<div class="line"><a name="l00257"></a><span class="lineno">  257</span>&#160;            ++stkptr;</div>
<div class="line"><a name="l00258"></a><span class="lineno">  258</span>&#160;        }                           <span class="comment">/* save big recursion for later */</span></div>
<div class="line"><a name="l00259"></a><span class="lineno">  259</span>&#160; </div>
<div class="line"><a name="l00260"></a><span class="lineno">  260</span>&#160;        <span class="keywordflow">if</span> (loguy &lt; hi) {</div>
<div class="line"><a name="l00261"></a><span class="lineno">  261</span>&#160;            lo = loguy;</div>
<div class="line"><a name="l00262"></a><span class="lineno">  262</span>&#160;            <span class="keywordflow">goto</span> recurse;           <span class="comment">/* do small recursion */</span></div>
<div class="line"><a name="l00263"></a><span class="lineno">  263</span>&#160;        }</div>
<div class="line"><a name="l00264"></a><span class="lineno">  264</span>&#160;    }</div>
<div class="line"><a name="l00265"></a><span class="lineno">  265</span>&#160;    <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00266"></a><span class="lineno">  266</span>&#160;        <span class="keywordflow">if</span> (loguy &lt; hi) {</div>
<div class="line"><a name="l00267"></a><span class="lineno">  267</span>&#160;            lostk[stkptr] = loguy;</div>
<div class="line"><a name="l00268"></a><span class="lineno">  268</span>&#160;            histk[stkptr] = hi;</div>
<div class="line"><a name="l00269"></a><span class="lineno">  269</span>&#160;            ++stkptr;               <span class="comment">/* save big recursion for later */</span></div>
<div class="line"><a name="l00270"></a><span class="lineno">  270</span>&#160;        }</div>
<div class="line"><a name="l00271"></a><span class="lineno">  271</span>&#160; </div>
<div class="line"><a name="l00272"></a><span class="lineno">  272</span>&#160;        <span class="keywordflow">if</span> (lo &lt; higuy) {</div>
<div class="line"><a name="l00273"></a><span class="lineno">  273</span>&#160;            hi = higuy;</div>
<div class="line"><a name="l00274"></a><span class="lineno">  274</span>&#160;            <span class="keywordflow">goto</span> recurse;           <span class="comment">/* do small recursion */</span></div>
<div class="line"><a name="l00275"></a><span class="lineno">  275</span>&#160;        }</div>
<div class="line"><a name="l00276"></a><span class="lineno">  276</span>&#160;    }</div>
<div class="line"><a name="l00277"></a><span class="lineno">  277</span>&#160;  }</div>
<div class="line"><a name="l00278"></a><span class="lineno">  278</span>&#160; </div>
<div class="line"><a name="l00279"></a><span class="lineno">  279</span>&#160;  <span class="comment">/* We have sorted the array, except for any pending sorts on the stack.</span></div>
<div class="line"><a name="l00280"></a><span class="lineno">  280</span>&#160;<span class="comment">      Check if there are any, and do them. */</span></div>
<div class="line"><a name="l00281"></a><span class="lineno">  281</span>&#160; </div>
<div class="line"><a name="l00282"></a><span class="lineno">  282</span>&#160;  --stkptr;</div>
<div class="line"><a name="l00283"></a><span class="lineno">  283</span>&#160;  <span class="keywordflow">if</span> (stkptr &gt;= 0) {</div>
<div class="line"><a name="l00284"></a><span class="lineno">  284</span>&#160;      lo = lostk[stkptr];</div>
<div class="line"><a name="l00285"></a><span class="lineno">  285</span>&#160;      hi = histk[stkptr];</div>
<div class="line"><a name="l00286"></a><span class="lineno">  286</span>&#160;      <span class="keywordflow">goto</span> recurse;           <span class="comment">/* pop subarray from stack */</span></div>
<div class="line"><a name="l00287"></a><span class="lineno">  287</span>&#160;  }</div>
<div class="line"><a name="l00288"></a><span class="lineno">  288</span>&#160;  <span class="keywordflow">else</span></div>
<div class="line"><a name="l00289"></a><span class="lineno">  289</span>&#160;      <span class="keywordflow">return</span>;                 <span class="comment">/* all subarrays done */</span></div>
<div class="line"><a name="l00290"></a><span class="lineno">  290</span>&#160;}</div>
<div class="line"><a name="l00291"></a><span class="lineno">  291</span>&#160; </div>
<div class="line"><a name="l00292"></a><span class="lineno">  292</span>&#160;<span class="preprocessor">#undef ON_QSORT_GT</span></div>
<div class="line"><a name="l00293"></a><span class="lineno">  293</span>&#160;<span class="preprocessor">#undef ON_QSORT_LE</span></div>
<div class="line"><a name="l00294"></a><span class="lineno">  294</span>&#160;<span class="preprocessor">#undef ON_QSORT_EQ</span></div>
<div class="line"><a name="l00295"></a><span class="lineno">  295</span>&#160;<span class="preprocessor">#undef ON_QSORT_SWAP</span></div>
<div class="line"><a name="l00296"></a><span class="lineno">  296</span>&#160;<span class="preprocessor">#undef ON_QSORT_CUTOFF</span></div>
<div class="line"><a name="l00297"></a><span class="lineno">  297</span>&#160;<span class="preprocessor">#undef ON_QSORT_STKSIZ</span></div>
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